Pictures show u have to solve and the answers
" 0.83 " MEANS " 83/100 ". They are identical quantities, because they are the SAME quantity.
The answer is 2 x10 = 20
To the power of b which is 15
D = 545.79
r = 48.3
Plug in numbers to corresponding variables
545.79 = t(48.3)
Isolate the t, divide 48.3 from both sides
(545.79)/48.3 = 48.3t/48.3
t = 545.79/48.3
t = 11.3
t = A) 11.3 h
hope this helps