Concrete used for playground equipment is typically a special type of high-strength, durable concrete designed specifically for outdoor use. This type of concrete is often reinforced with steel to provide additional strength and stability. It is also formulated to withstand the elements, including exposure to moisture, temperature changes, and heavy use. Additionally, the concrete used for playground equipment is often textured or finished to provide a non-slip surface for safety. **

Teachers work with a variety of tools, materials, and equipment in their daily work. Some common tools include whiteboards, markers, and projectors for delivering lessons. Materials such as textbooks, worksheets, and manipulatives are used to support student learning. Equipment like computers, printers, and audio-visual devices are also essential for creating engaging lessons and activities. Overall, teachers rely on a combination of traditional and modern tools to effectively educate their students. **

You can use a variety of materials to make lean concrete, including cement, sand, water, and coarse aggregates such as gravel or crushed stone. The proportions of these materials can be adjusted to achieve the desired strength and workability of the concrete. Additionally, admixtures such as fly ash or slag can be added to improve the properties of the lean concrete. It's important to carefully measure and mix these materials to ensure the quality and consistency of the lean concrete. **

Teachers work with a variety of tools, materials, and equipment in their daily tasks. Some common tools include computers, projectors, whiteboards, and pens. Materials can range from textbooks and worksheets to art supplies and science equipment. Additionally, teachers may use equipment such as printers, laminators, and document cameras to enhance their teaching methods and create engaging learning experiences for students. **

To apply concrete on concrete, the existing surface must be clean, free of debris, and properly moistened. A bonding agent or primer should be applied to the existing concrete to ensure adhesion. The fresh concrete mix can then be poured or pumped onto the existing surface and spread evenly using a screed or trowel. It is important to properly cure the new concrete to prevent cracking and ensure a strong bond between the two layers. **

Yes, it is possible to pour new concrete over old concrete as long as the existing concrete is in good condition and properly prepared. The old concrete should be clean, free of any loose debris, and roughened to provide a good bonding surface for the new concrete. Additionally, a bonding agent may be used to ensure a strong bond between the old and new concrete. It is important to consult with a professional to assess the condition of the existing concrete and determine the best approach for pouring new concrete over it. **

For setting lawn edging stones, garden concrete would be the better option. Garden concrete is specifically designed for outdoor use and is more durable and weather-resistant than concrete screed. It also has better adhesion properties, making it more suitable for securing the edging stones in place. Additionally, garden concrete is often formulated to be more resistant to cracking and shifting, which is important for maintaining the integrity of the lawn edging. **

It is unclear whether the concrete belt was poured with the wrong concrete based on the information provided. To determine if the wrong concrete was used, further investigation would be needed to compare the specifications of the concrete used with the requirements for the project. Factors such as strength, composition, and curing methods would need to be considered to determine if the concrete used was indeed incorrect. **