Step 1: Understand the concept of rank and determinant.
The rank of a matrix is the maximum number of linearly independent rows (or columns). If a \(3 \times 3\) matrix has rank less than 3, its rows (or columns) are linearly dependent.
Step 2: Relation between rank and determinant.
If the rank of a square matrix is less than its order (here, less than 3), then its determinant is zero.
An electricity utility company charges ₹7 per kWh. If a 40-watt desk light is left on for 10 hours each night for 180 days, what would be the cost of energy consumption? If the desk light is on for 2 more hours each night for the 180 days, what would be the percentage-increase in the cost of energy consumption?