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Alivestock company reports that the mean weight of a group of young steers is 1100 pounds with a standard deviation of 93 pounds. based on the model n(1100,93) for the weights of steers, what percent of steers weigh a) over 1050 pounds? b) under 1300 pounds? c) between 1150 and 1250 pounds?

Ineed to answer this problem but i lack in knowledge, what should i study to answer this problem? i have never used derivatives in a physics problem so i'm not sure what's happening and i can't find videos explaining.

What is the volume of 2400kg of gasoline (petrol) if the density of petrol is 0.7g/km3