Answer:
70 x 4
Explanation:
To round to one significant figure we have to round each numbers to the first numbers greater than 0
To round 74.5 to 1sf we have to round it to the nearest 10. As the number next to it (4) is less than 5 we will round down to 70
To round 3.6 to 1sf we have to round to the nearest whole number. As the number next to it (6) is greater than 5 we will round up to 4
Hope this helps, have a great day!