Following data are given for designing a Portland cement concrete mix for a nonstructural sidewalk slab: Design strength fc=39MPa - Standard deviation of fc obtained from 22 tests =1.4MPa - Normal condition, no freezing and thawing - Use air entrained concrete - Slab thickness =300mm - Fineness modulus of fine aggregate =2.5 - Maximum aggregate size =50mm and nominal maximum aggregate size =37.5mm - Bulk oven-dry specific gravity of coarse aggregate =2.6 - Oven-dry rodded density of coarse aggregate =2002kg/m3 - Type I cement, relative density=3.1 Find the followings: a. Required compressive strength ( 0.2 points) b. w/c ratio ( 0.2 points) c. Coarse aggregate amount (kg/m3)(0.2 points) d. If the w/c ratio is 10% reduced, will the quantity of coarse aggregate increase, decrease or remain the same? Explain your answer. (0.1 points)