Please help I really need help/

The area (a) of a circle with a radius of r is given by the formula and its diameter (d) is given by d=2r. arrange the equations in the correct sequence to rewrite the formula for diameter in terms of the area of the circle.

Taber invested money in an account where interest is compounded every year.he made no withdrawals or deposits. the function a(t)=525(1+0.05)^t represent the amount of money in the account after t years. how much money did taber origanally invested?

Luisa sells stuffed animals. she sells her stuffed elephant for $34.90, and the sales tax is 6% of the sale price. about how much is the sales tax on the elephant?