Gallium is a solid metal at room temperature, but it will melt into a liquid in your hand

Question: Gallium is a solid metal at room temperature, but it will melt into a liquid in your hand. The melting point of gallium is 85.6 °F. What is this temperature on (a) the celsius and (b) the Kelvin scale?

With using the formula provided for Celsius in chapter 1.2, I calculated the answer of 29.78°C.

I had to first find the answer for Celsius first since the Fahrenheit was provided. Once I calculated the Celsius I then plugged it into the Kelvin formula provided in the book and came up with the answer of 302.93K.

For the Cumulative Problem #71:

Do each calculation without using your calculator and give the answers to the correct number of significant figures.

There was three different equations:

(a) 1.76 X 10^-3 / 8.0 X 10²

(b) 1.87 X 10^-2 + 2 X 10^-4 – 3.0 X 10^-3

(c) [(1.36 X 10⁵)(0.000322)/(0.082)](129.2)

I had difficulty completely these problems, well manly with number 3. I did get the following answers even though I have no faith in my answer for (c).

(a) 2.2 X 10^-7

(b) 1.59 X 10^-1

(c) 6.8999 X 10⁴