1. What is the mass of a 4-pound weight? 2. Manning's equation is given below for English units. Q is discharge in ft/s, n is dimensionless, A is the channel cross-sectional area in square ft, P is the wetted perimeter in feet, and S is the channel slope which is dimensionless. a. What are the units of 1.486? b. For the metric version of Manning's equation what does the constant 1.486 become? Q= 1.486 A5/3 n p S1 3. In statistics the probability density function f(x) of a continuously distributed random variable x and the probability distribution function P(x) are related as follows. If x has units of meters, what are the units off? P(x)= f(u)du