Question $4$ only please A $5m$ model of a $180m$ long ship is towed in a tank at a speed of $1\mathrm{.}2\frac{m}{s}.$ The

measured resistance of the model is $11\mathrm{.}8N.$ Assuming $60\%$ of the resistance is because

of skin friction $($both for the model and the prototype$),$ calculate the resistance of the ship

at the speed corresponding to Froude number similitude. The wetted surface area of the

ship is $3600m^2.$

Repeat Prob. $3,$ this time deleting the phrase "Assuming $60\%$ of the resistance is

because of skin friction $($both for the model and the protolypc$)..."$ Instead, use Froude's

method and calculate the frictional resistance of the model and prototype using the ITTC

$\text{'}57$ equation. Compare your results to the result of Prob. $3.$