Question 1 (ii)
Simplify combining like terms:
−z2+13z2−5z+7z3−15z
Question 13 Write the molecular formulae of all the compounds that can be formed by the combination of following ions Cu2+,Na+,Fe3+,Cl−,SO24,PO3−4
The mode of the given data 7, 9, 11, 13, 9 13, 9, 9, 7, 8 is