Easy 25 points answer soon please

What is the y intercept of f(x)=(1/2)^x?

The trigonometric ratios sine and secant are reciprocals of each other

Diane’s bank is offering 5% interest, compounded monthly. if diane invests $10,500 and wants $20,000 when she withdrawals, how long should she keep her money in for? round to the nearest tenth of a year.