Martin was 10 years old last year. This year, His brother's age is 2 times of Martin's. How old is Martin's brother this year?​

If 1/√5+1/√5+1=p+q√r , find the values of p, q and r

Sketch one cycle if the cosine function y=2cos2theta

The two cylinders are similar. if the ratio of their surface areas is 9/1.44 find the volume of each cylinder. round your answer to the nearest hundredth. a. small cylinder: 152.00 m3 large cylinder: 950.02 m3 b. small cylinder: 972.14 m3 large cylinder: 12,924.24 m3 c. small cylinder: 851.22 m3 large cylinder: 13,300.25 m3 d. small cylinder: 682.95 m3 large cylinder: 13,539.68 m3