First, you much find out how many houses are deliverd in 1 hour.
130/2.5=52
So 52 houses are delivered in 1 hour. Now, divide that by 312.
312/52=6
It would take 6 hours to deliver 312 houses.
D = m / V
<span>m = 1.26 g </span>
<span>V = s^3 = 4.1^3 = 68.921 cm^3 </span>
<span>so </span>
<span>D = 12.6 / 68.921 = 0.1828 g/cm^3 </span>
<span>and this corresponds to choice (a)
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For this you will have to make a tree diagram
it will be so much easier although there is a way to do it
probability of getting heads is = 1/2 there for 10 tosses its (1/20)^10
Eight thousandths and eight hundredths
