Help please math algebra

How can you check that you have correctly converted frequencies to relative frequencies?

Use a standard normal table to determine the probability. give your answer as a decimal to four decimal places. −1.5< < 1.5)

Adriana had a garden where he measured the height of a corn plant. what. on the first day,it was 145 cm tall.after 2 weeks is grew by 23 cm.what is the height of the corn plant