Which of the following situations may cause someone to use substitution, in order to solve a system of equations?

a. an exact solution is not needed.
b. one of the equations may easily be solved for a variable.
c. an exact solution is needed.
d. both of the equations are solved for one variable.

Choose a second initial value that is 0.01 greater than the initial value from question 9. iterate it using the function, f, ten times. if necessary, you can round your results to the nearest ten-thousandth.

Alicia puts $400 in a bank account. each year the account earns 5% simple interest. how much money will be in her bank account in six months?

Aspacecraft can attain a stable orbit 300 kilometers above earth if it reaches a velocity of 7.7 kilometers per second. the formula for a rocket's maximum velocity v in kilometers per second is vequalsminus0.0098tplusc ln upper r, where t is the firing time in seconds, c is the velocity of the exhaust in kilometers per second, and r is the ratio of the mass of the rocket filled with fuel to the mass of the rocket without fuel. find the velocity of a spacecraft whose booster rocket has a mass ratio of 20, an exhaust velocity of 2.1 km/s, and a firing time of 15 s. can the spacecraft achieve a stable orbit 300 km above earth?