Ireally need with this last one i don't understand this one at all

)a smart phone has dimensions of 4.9 inches (height), 2.3 inches (width) and 8.0 millimeters (depth). what is the volume of the smart phone in cubic centimeters? (1 in = 2.54 cm)

On new year's day, the average temperature of a city is 5.7 degrees celsius. but for new year's day 2012, the temperature was 9.8 degrees below the average. i) if a represents the average temperature on new year's day and 7 represents the temperature on new year's day 2012, what formula accurately relates the two values together? ii) what was the temperature on new year's day 2012? dt a 0.8 ii) - 4 1 degrees celsius da-t-98 ii) 59 degrees celsius 1) 7 = -9,8 11) 59 degrees celsius ii) l degrees celsius

Given the two similar triangles, how do i find the missing length? if a=4, b=5, and b'=7.5 find a'