The manager of a grocery store has taken a random sample of 100 customers. the average length of time it took these 100 customers to check out was 3 minutes. it is known that the standard deviation of the population of checkout times is 1 minute. the standard error of the mean equals?

The standard error of the mean equals 0.1            

Step-by-step explanation:

We are given the following in the question:

Sample mean, = 3 minutes

Sample size, n = 100

Population standard deviation, σ = 1 minute

Formula:

Thus, standard error of the mean equals 0.1

intensity of the vector is v= √37 ≈ 6.08 units and make angle ∡α ≈ 9.46° with east direction

step-by-step explanation:

required vector is consists of the two componentsvx= 2+4=6 units   and vy= 1 unit and vx ⊥ vywe will use pythagorian theorem to find intensity of the vector vv∧2 = vx∧2 + vy∧2 => v = √vx∧2 + vy∧2 = √6∧2 + 1∧2 = √36+1 = √37 ≈ 6.08 unitsthe angle ∡α between vector and east direction we wil find with tanαtanα = 1/6 => α = arc tanα = arc 1/6 => α ≈ 9.46°

hope this

-13

step-by-step explanation:

f(x)=2x-5 for f(-4)

f(-4)   means let x=-4

f(-4) = 2(-4) -5

f(-4) =-8-5

      = -13