WASHINGTON (AP) — President Joe Biden is putting into play his national COVID-19 strategy to ramp up vaccinations and testing, reopen schools and businesses and increase the use of masks — including a requirement that Americans mask up for travel. He’ll sign 10 virus-related executive orders on Thursday as the nation is deep in the deadliest wave of the pandemic and facing worrisome new mutations. Biden has vowed to take more aggressive measures than his predecessor to contain the virus, but he faces steep obstacles, including uncertainty over whether congressional Republicans will help pass his $1.9 trillion coronavirus package.