Formal or Informal Tone

Is this expression formal or informal? I've been monitoring your progress carefully. A) formal B) informal

Is this expression formal or informal? I'm watching how you're getting on. A) formal B) informal

Is this expression formal or informal? That's great, thanks. A) formal B) informal

"Employ" is more formal than "use". TRUE or FALSE

Is this expression formal, neutral or informal? Hi, where's the best cafe round here? A) formal B) neutral C)informal

"Say no" is more informal than "decline". TRUE or FALSE

Is this expression formal or informal? I'd be very grateful if you could ... A) formal B) informal

Is this expression formal or informal? Could you direct me to a good quality cafe please? A) formal B) neutral C) informal

"Endevour" is more informal than "have a go at". TRUE or FALSE

Is this expression formal, neutral or informal? Hi, do you know where the best cafe is around here? A) formal B) neutral C) informal