question about resetting a digital clock at 12

[rancidrancid676]

hi, im buliding a digital clock in my electronics class. i have the clock working up to resetting the hours at 12. counting for the minutes, i am using an lm74160 and an lm7493. for the hours, 3 lm7476's (two for 0-9, and one for 0-1) . the lm7476's (jk flipflops 6 total) are counting asynchronously and i am unable to figure out how to make the first set of flip flops counting 0-9 to reset at both 9 and at 2 when the second set of flipflops is at one making a count of 12. please help if you know anything.