100 X 100 Multiplication Charts Can You Help Me With These 3 Science Questions?

Can you help me with these 3 science questions? - 100 x 100 multiplication charts

To multiply or divide, you can not answer your points more than the smallest number of significant figures for the problem.

100.0 GX (1.00 cal / gx ° C) x 28.6 ° C

X is the multiplication

Around the answer to an appropriate number of significant figures.

2.00 x 10 ^ 2 GX (1 cal / gx ° C) x 28.6 ° C

Round the following numbers for the appropriate number of significant digits.

739.51 (3 significant figures)