What type of device is a coal-fired power plant?

An astronomer at the equator measures the doppler shift of sunlight at sunset. from this, she calculates that earth’s tangential velocity at the equator is 465 m/s. the centripetal acceleration at the equator is 3.41  10 2 m/s 2 . use this data to calculate earth’s radius.

Which of the following is not am example of a polymer? protein nylon kevlar concreta

Ineed the answer to question 1 , i’m desperate