Can someone please help me I don’t understand what to do

Fredrick designed an experiment in which he spun a spinner 20 times and recorded the results of each spin

1. ∠1 is complementary to ∠2 and ∠3 is complementary to ∠2. subtraction property of equality 2. m∠1 + m∠2 = 90 and m∠3 + m∠2 = 90 substitution 3. m∠1 + m∠2 = m∠3 + m∠2 definition of complementary 4. m∠1 = m∠3 given

Asequence is a function whose is the set of natural numbers