Determine the value of the integer variable counter after execution of the following program segment. (Here i, j, k, l, m, and n are integer variables. The variables r, s, and t are also integer variables; their values - where r ≥ 1, s ≥ 5, and t ≥ 7 - have been set prior to this segment.)
counter : = 10
for i : = 1 to 12 do
for j : = 1 to r do
counter : = counter + 2
for k : = 5 to s do
for 1 : = 3 to k do
counter : = counter + 4
for m : = 3 to 12 do
counter : = counter + 6
for n : = t down to 7 do
counter : = counter + 8