Use reciprocal identities to rewrite the expressions in terms of one functions. Help?? Asap

Suppose your school costs for this term were $4900 and financial aid covered 3/4 of that amount. how much did financial aid cover? and how much do you still have to pay?

Look at the figure below: triangle abc is a right triangle with angle abc equal to 90 degrees. the length of ac is 5 units and the length of ab is 4 units. d is a point above c. triangle adc is a right triangle with angle dac equal to 90 degrees and dc parallel to ab. what is the length, in units, of segment cd?

When steve woke up. his temperature was 102 degrees f. two hours later it was 3 degrees lower. what was his temperature then?