$(10\%)7.$ Loads required to crush six $150150mm$ cube specimens and three $150300mm$ cylinder specimens cast from the same concrete under compression are given below.

a$)$ Determine the average cylinder and cube compressive strength of test specimens, respectively.

b$)$ Suggest a conversion factor between cube and cylinder compressive strength.

$\backslash$table$[[$Cylinders$,$Load $($kN$)],[$Specimen $1,530],[$Specimen $2,540],[$Specimen $3,565]]$

$\backslash$table$[[$Cubes$,$Load $(kN)$