The leaf shows New Year's Day of 2030. On which day of the week will New Year's Day of 2050 fall?

From 1 Jan 2030 to 1 Jan 2050 is 20 years containing the leap years 2032, 2036, 2040, 2044 and 2048: 5. Odd days $=20+5=25=3\times 7+4$. Tuesday + 4 = Saturday. (Friday forgets one leap year; Tuesday ignores the leap years and treats 20 as a multiple of 7.)