Atriangle in which one angle is acute cannot have an acute exterior angle. true or false

This is false because the problem is talking about the entire triangle and not just one angle. This means that another angle of the triangle could be obtuse which would make an exterior angle of that triangle acute. I hope this helps. please give me a crown and a like if you think I deserve it and if you have other questions friend me and ask them. 

40 & 50 in the right corner are the complementary angles as when placed in a sum (added together) they make 90°