Weegy: The stars that have pulsation periods between 1.5 hours and 1.2 days are C. [ RR Lyrae variables
"Their period is shorter, typically less than one day, sometimes ranging down to seven hours."
The others :
A. Cepheid variables - have periods of many days
B. Protostars - are variable in the T-Tauri stage, but they are very hard to observe for most observers and period is longer
D. Nebulas - a nebula is not a star ] User: ... (More)