Negative allowance is provided on the pattern to take care of

Molten aluminium was poured in a sand mold and the thickness of solid skin formed after $$20$$ seconds and $$50$$ seconds were fond to be $$3mm$$ and $$4.5mm$$ respectively. What would be the thickness of the solid skin at the end of $$100$$ seconds after pouring?

Shrinkage allowance on pattern is provided to compensate for shrinkage when

What is the velocity of the steel at the bottom of the sprue if the sprue height is $$30$$ $$cm$$? Assume the frictional and other losses to be $$20\% $$