Final answer:
Without additional context, it's unclear which two new skills were learned on day 1, but 'Crossover and side straddle' are common jump rope skills that might be taught.
Step-by-step explanation:
The question seems to be about the skills learned in a physical education class, specifically those related to activities such as jump rope or gymnastics. Without additional context, it is difficult to definitively answer which skills were learned on day 1, as this is dependent on the curriculum and the specific lesson plan used by the educator. However, based on the options provided, 'b) Crossover and side straddle' typically refer to jump rope skills, while 'a) Double-jump and double Dutch' could either refer to jump rope or gymnastic activities. Options 'c) Up and down' and 'd) Not covered' are less specific and could apply to a variety of activities.