Chemistry - Are my answers correct [SIG FIG] ?

Question

Use exponential notation to express the number 480 to

a. 1 sig fig

b. 2 sig fig

c. 3 sig fig

d. 4 sig fig

a. 400

b. 480

c. 480. <---- notice the dot after zero

d. 480.0

Answer 1

a. 5 x 10^2

b. 4.8 x 10^2

c. 4.80 x 10^2

d. 4.800 x 10^2

Answer 2

Yes except for the exponential function. Also round off the 1st answer to 5