3.1 Write the following in scientific notation
a) 217 000 000 b) 0,000 253​

2.17 x 10^8

0.253 x 10^-4 if number is 0.000253 or 2.53 x 10^2 if number is 253

Step-by-step explanation:

answer: 7 x 2/5 = 2.8 hours, is your answer. your welcome! : 3

step-by-step explanation: first work out how long it took to hose 1/7 of the lawn which is 2/5 hours. times that by 7 to get the whole lawn.

sorry i don't know the other answer. i didn't learn what a proportional relationship is.