Một hộp đựng 10 quả cầu gồm: 2 quả màu đỏ, 3 quả màu vàng và 5 quả màu xanh. Chọn ngẫu nhiên từ hộp đó ra 4 quả cầu. Tính xác suất chọn được 2 quả màu
xanh.

If t8 = 4 and t12 = −2, find the first three terms of the arithmetic sequence.

Algebraically prove that a clockwise and counterclockwise rotation of 180° about the origin for triangle abc are equivalent rotations.

Perry angelo is planning to open a restaurant. he has the resources to produce and sell either hamburgers or pizzas. so he does some research and finds that the new location has a good demand for pizza. he hires cooks, wait staff, and an accounts person for his new pizzeria. he also arranges for materials such as pizza ingredients and pizza boxes. determine three factors affecting perry's cost of making pizza. write down the name of the factors and their instances in this scenario.