निम्नलिखित में से कौन-सा 'बीजगणित' (algebra) सीखने का एक मूलभूत या मुख्य प्रक्रियात्मक पहलू नहीं है?

Why is it important for a child to apply and implement practically all that has been learnt?

When students read books or texts primarily for pleasure and general enjoyment, they are engaged in: