Question

red glass contains small amount of 1 uo2 2 coO 3 au and cu 4 fe2o3 ​

Answer 1

Answer:

394

it is answer

make be a brainlest

Answer 2

Explanation:

9. A school organized a competition of making and decorating pen holders in the shape of a cylinder by making its base and its curved surface area with cardboard. Each pen holder is supposed to have a radius of 3.5 cm and height 10 cm. How much cardboard does the school need if 30 students are participating in the competition