How do i write an equation that represents the line

How to find the exponential function y=ca^x, with points (1,2) and (2,1)

Write the expression as a single natural logarithm. 2 in a - 4 in y

The evening newspaper is delivered at a random time between 5: 30 and 6: 30 pm. dinner is at a random time between 6: 00 and 7: 00 pm. each spinner is spun 30 times and the newspaper arrived 19 times before dinner. determine the experimental probability of the newspaper arriving before dinner.