Final answer:
The measure of angle l' after a dilation with a scale factor of 1/2 remains unchanged at 70 degrees.
Step-by-step explanation:
The student asked about the measure of ∆l' after a dilation with a scale factor of k=1/2. It is important to note that dilation affects the size of a figure but not the measures of its angles. Therefore, no matter what the scale factor is, the angle measures in a figure remain unchanged after dilation. Since we are given that m∠l=70 degrees in ∆lmn, the measure of ∆l' after dilation would also be 70 degrees.